/* * linux/fs/nfs/nfs2xdr.c * * XDR functions to encode/decode NFS RPC arguments and results. * * Copyright (C) 1992, 1993, 1994 Rick Sladkey * Copyright (C) 1996 Olaf Kirch * 04 Aug 1998 Ion Badulescu <ionut@cs.columbia.edu> * FIFO's need special handling in NFSv2 */ #include <linux/param.h> #include <linux/time.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/errno.h> #include <linux/string.h> #include <linux/in.h> #include <linux/pagemap.h> #include <linux/proc_fs.h> #include <linux/sunrpc/clnt.h> #include <linux/nfs.h> #include <linux/nfs2.h> #include <linux/nfs_fs.h> #include "internal.h" #define NFSDBG_FACILITY NFSDBG_XDR /* Mapping from NFS error code to "errno" error code. */ #define errno_NFSERR_IO EIO /* * Declare the space requirements for NFS arguments and replies as * number of 32bit-words */ #define NFS_fhandle_sz (8) #define NFS_sattr_sz (8) #define NFS_filename_sz (1+(NFS2_MAXNAMLEN>>2)) #define NFS_path_sz (1+(NFS2_MAXPATHLEN>>2)) #define NFS_fattr_sz (17) #define NFS_info_sz (5) #define NFS_entry_sz (NFS_filename_sz+3) #define NFS_diropargs_sz (NFS_fhandle_sz+NFS_filename_sz) #define NFS_removeargs_sz (NFS_fhandle_sz+NFS_filename_sz) #define NFS_sattrargs_sz (NFS_fhandle_sz+NFS_sattr_sz) #define NFS_readlinkargs_sz (NFS_fhandle_sz) #define NFS_readargs_sz (NFS_fhandle_sz+3) #define NFS_writeargs_sz (NFS_fhandle_sz+4) #define NFS_createargs_sz (NFS_diropargs_sz+NFS_sattr_sz) #define NFS_renameargs_sz (NFS_diropargs_sz+NFS_diropargs_sz) #define NFS_linkargs_sz (NFS_fhandle_sz+NFS_diropargs_sz) #define NFS_symlinkargs_sz (NFS_diropargs_sz+1+NFS_sattr_sz) #define NFS_readdirargs_sz (NFS_fhandle_sz+2) #define NFS_attrstat_sz (1+NFS_fattr_sz) #define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz) #define NFS_readlinkres_sz (2) #define NFS_readres_sz (1+NFS_fattr_sz+1) #define NFS_writeres_sz (NFS_attrstat_sz) #define NFS_stat_sz (1) #define NFS_readdirres_sz (1) #define NFS_statfsres_sz (1+NFS_info_sz) /* * Common NFS XDR functions as inlines */ static inline __be32 * xdr_encode_fhandle(__be32 *p, const struct nfs_fh *fhandle) { memcpy(p, fhandle->data, NFS2_FHSIZE); return p + XDR_QUADLEN(NFS2_FHSIZE); } static inline __be32 * xdr_decode_fhandle(__be32 *p, struct nfs_fh *fhandle) { /* NFSv2 handles have a fixed length */ fhandle->size = NFS2_FHSIZE; memcpy(fhandle->data, p, NFS2_FHSIZE); return p + XDR_QUADLEN(NFS2_FHSIZE); } static inline __be32* xdr_encode_time(__be32 *p, struct timespec *timep) { *p++ = htonl(timep->tv_sec); /* Convert nanoseconds into microseconds */ *p++ = htonl(timep->tv_nsec ? timep->tv_nsec / 1000 : 0); return p; } static inline __be32* xdr_encode_current_server_time(__be32 *p, struct timespec *timep) { /* * Passing the invalid value useconds=1000000 is a * Sun convention for "set to current server time". * It's needed to make permissions checks for the * "touch" program across v2 mounts to Solaris and * Irix boxes work correctly. See description of * sattr in section 6.1 of "NFS Illustrated" by * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5 */ *p++ = htonl(timep->tv_sec); *p++ = htonl(1000000); return p; } static inline __be32* xdr_decode_time(__be32 *p, struct timespec *timep) { timep->tv_sec = ntohl(*p++); /* Convert microseconds into nanoseconds */ timep->tv_nsec = ntohl(*p++) * 1000; return p; } static __be32 * xdr_decode_fattr(__be32 *p, struct nfs_fattr *fattr) { u32 rdev, type; type = ntohl(*p++); fattr->mode = ntohl(*p++); fattr->nlink = ntohl(*p++); fattr->uid = ntohl(*p++); fattr->gid = ntohl(*p++); fattr->size = ntohl(*p++); fattr->du.nfs2.blocksize = ntohl(*p++); rdev = ntohl(*p++); fattr->du.nfs2.blocks = ntohl(*p++); fattr->fsid.major = ntohl(*p++); fattr->fsid.minor = 0; fattr->fileid = ntohl(*p++); p = xdr_decode_time(p, &fattr->atime); p = xdr_decode_time(p, &fattr->mtime); p = xdr_decode_time(p, &fattr->ctime); fattr->valid |= NFS_ATTR_FATTR_V2; fattr->rdev = new_decode_dev(rdev); if (type == NFCHR && rdev == NFS2_FIFO_DEV) { fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO; fattr->rdev = 0; } return p; } static inline __be32 * xdr_encode_sattr(__be32 *p, struct iattr *attr) { const __be32 not_set = __constant_htonl(0xFFFFFFFF); *p++ = (attr->ia_valid & ATTR_MODE) ? htonl(attr->ia_mode) : not_set; *p++ = (attr->ia_valid & ATTR_UID) ? htonl(attr->ia_uid) : not_set; *p++ = (attr->ia_valid & ATTR_GID) ? htonl(attr->ia_gid) : not_set; *p++ = (attr->ia_valid & ATTR_SIZE) ? htonl(attr->ia_size) : not_set; if (attr->ia_valid & ATTR_ATIME_SET) { p = xdr_encode_time(p, &attr->ia_atime); } else if (attr->ia_valid & ATTR_ATIME) { p = xdr_encode_current_server_time(p, &attr->ia_atime); } else { *p++ = not_set; *p++ = not_set; } if (attr->ia_valid & ATTR_MTIME_SET) { p = xdr_encode_time(p, &attr->ia_mtime); } else if (attr->ia_valid & ATTR_MTIME) { p = xdr_encode_current_server_time(p, &attr->ia_mtime); } else { *p++ = not_set; *p++ = not_set; } return p; } /* * NFS encode functions */ /* * Encode file handle argument * GETATTR, READLINK, STATFS */ static int nfs_xdr_fhandle(struct rpc_rqst *req, __be32 *p, struct nfs_fh *fh) { p = xdr_encode_fhandle(p, fh); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Encode SETATTR arguments */ static int nfs_xdr_sattrargs(struct rpc_rqst *req, __be32 *p, struct nfs_sattrargs *args) { p = xdr_encode_fhandle(p, args->fh); p = xdr_encode_sattr(p, args->sattr); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Encode directory ops argument * LOOKUP, RMDIR */ static int nfs_xdr_diropargs(struct rpc_rqst *req, __be32 *p, struct nfs_diropargs *args) { p = xdr_encode_fhandle(p, args->fh); p = xdr_encode_array(p, args->name, args->len); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Encode REMOVE argument */ static int nfs_xdr_removeargs(struct rpc_rqst *req, __be32 *p, const struct nfs_removeargs *args) { p = xdr_encode_fhandle(p, args->fh); p = xdr_encode_array(p, args->name.name, args->name.len); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Arguments to a READ call. Since we read data directly into the page * cache, we also set up the reply iovec here so that iov[1] points * exactly to the page we want to fetch. */ static int nfs_xdr_readargs(struct rpc_rqst *req, __be32 *p, struct nfs_readargs *args) { struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth; unsigned int replen; u32 offset = (u32)args->offset; u32 count = args->count; p = xdr_encode_fhandle(p, args->fh); *p++ = htonl(offset); *p++ = htonl(count); *p++ = htonl(count); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); /* Inline the page array */ replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readres_sz) << 2; xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, args->pgbase, count); req->rq_rcv_buf.flags |= XDRBUF_READ; return 0; } /* * Decode READ reply */ static int nfs_xdr_readres(struct rpc_rqst *req, __be32 *p, struct nfs_readres *res) { struct kvec *iov = req->rq_rcv_buf.head; size_t hdrlen; u32 count, recvd; int status; if ((status = ntohl(*p++))) return nfs_stat_to_errno(status); p = xdr_decode_fattr(p, res->fattr); count = ntohl(*p++); res->eof = 0; hdrlen = (u8 *) p - (u8 *) iov->iov_base; if (iov->iov_len < hdrlen) { dprintk("NFS: READ reply header overflowed:" "length %Zu > %Zu\n", hdrlen, iov->iov_len); return -errno_NFSERR_IO; } else if (iov->iov_len != hdrlen) { dprintk("NFS: READ header is short. iovec will be shifted.\n"); xdr_shift_buf(&req->rq_rcv_buf, iov->iov_len - hdrlen); } recvd = req->rq_rcv_buf.len - hdrlen; if (count > recvd) { dprintk("NFS: server cheating in read reply: " "count %u > recvd %u\n", count, recvd); count = recvd; } dprintk("RPC: readres OK count %u\n", count); if (count < res->count) res->count = count; return count; } /* * Write arguments. Splice the buffer to be written into the iovec. */ static int nfs_xdr_writeargs(struct rpc_rqst *req, __be32 *p, struct nfs_writeargs *args) { struct xdr_buf *sndbuf = &req->rq_snd_buf; u32 offset = (u32)args->offset; u32 count = args->count; p = xdr_encode_fhandle(p, args->fh); *p++ = htonl(offset); *p++ = htonl(offset); *p++ = htonl(count); *p++ = htonl(count); sndbuf->len = xdr_adjust_iovec(sndbuf->head, p); /* Copy the page array */ xdr_encode_pages(sndbuf, args->pages, args->pgbase, count); sndbuf->flags |= XDRBUF_WRITE; return 0; } /* * Encode create arguments * CREATE, MKDIR */ static int nfs_xdr_createargs(struct rpc_rqst *req, __be32 *p, struct nfs_createargs *args) { p = xdr_encode_fhandle(p, args->fh); p = xdr_encode_array(p, args->name, args->len); p = xdr_encode_sattr(p, args->sattr); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Encode RENAME arguments */ static int nfs_xdr_renameargs(struct rpc_rqst *req, __be32 *p, struct nfs_renameargs *args) { p = xdr_encode_fhandle(p, args->fromfh); p = xdr_encode_array(p, args->fromname, args->fromlen); p = xdr_encode_fhandle(p, args->tofh); p = xdr_encode_array(p, args->toname, args->tolen); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Encode LINK arguments */ static int nfs_xdr_linkargs(struct rpc_rqst *req, __be32 *p, struct nfs_linkargs *args) { p = xdr_encode_fhandle(p, args->fromfh); p = xdr_encode_fhandle(p, args->tofh); p = xdr_encode_array(p, args->toname, args->tolen); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); return 0; } /* * Encode SYMLINK arguments */ static int nfs_xdr_symlinkargs(struct rpc_rqst *req, __be32 *p, struct nfs_symlinkargs *args) { struct xdr_buf *sndbuf = &req->rq_snd_buf; size_t pad; p = xdr_encode_fhandle(p, args->fromfh); p = xdr_encode_array(p, args->fromname, args->fromlen); *p++ = htonl(args->pathlen); sndbuf->len = xdr_adjust_iovec(sndbuf->head, p); xdr_encode_pages(sndbuf, args->pages, 0, args->pathlen); /* * xdr_encode_pages may have added a few bytes to ensure the * pathname ends on a 4-byte boundary. Start encoding the * attributes after the pad bytes. */ pad = sndbuf->tail->iov_len; if (pad > 0) p++; p = xdr_encode_sattr(p, args->sattr); sndbuf->len += xdr_adjust_iovec(sndbuf->tail, p) - pad; return 0; } /* * Encode arguments to readdir call */ static int nfs_xdr_readdirargs(struct rpc_rqst *req, __be32 *p, struct nfs_readdirargs *args) { struct rpc_task *task = req->rq_task; struct rpc_auth *auth = task->tk_msg.rpc_cred->cr_auth; unsigned int replen; u32 count = args->count; p = xdr_encode_fhandle(p, args->fh); *p++ = htonl(args->cookie); *p++ = htonl(count); /* see above */ req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); /* Inline the page array */ replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readdirres_sz) << 2; xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, 0, count); return 0; } /* * Decode the result of a readdir call. * We're not really decoding anymore, we just leave the buffer untouched * and only check that it is syntactically correct. * The real decoding happens in nfs_decode_entry below, called directly * from nfs_readdir for each entry. */ static int nfs_xdr_readdirres(struct rpc_rqst *req, __be32 *p, void *dummy) { struct xdr_buf *rcvbuf = &req->rq_rcv_buf; struct kvec *iov = rcvbuf->head; struct page **page; size_t hdrlen; unsigned int pglen, recvd; u32 len; int status, nr = 0; __be32 *end, *entry, *kaddr; if ((status = ntohl(*p++))) return nfs_stat_to_errno(status); hdrlen = (u8 *) p - (u8 *) iov->iov_base; if (iov->iov_len < hdrlen) { dprintk("NFS: READDIR reply header overflowed:" "length %Zu > %Zu\n", hdrlen, iov->iov_len); return -errno_NFSERR_IO; } else if (iov->iov_len != hdrlen) { dprintk("NFS: READDIR header is short. iovec will be shifted.\n"); xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen); } pglen = rcvbuf->page_len; recvd = rcvbuf->len - hdrlen; if (pglen > recvd) pglen = recvd; page = rcvbuf->pages; kaddr = p = kmap_atomic(*page, KM_USER0); end = (__be32 *)((char *)p + pglen); entry = p; /* Make sure the packet actually has a value_follows and EOF entry */ if ((entry + 1) > end) goto short_pkt; for (; *p++; nr++) { if (p + 2 > end) goto short_pkt; p++; /* fileid */ len = ntohl(*p++); p += XDR_QUADLEN(len) + 1; /* name plus cookie */ if (len > NFS2_MAXNAMLEN) { dprintk("NFS: giant filename in readdir (len 0x%x)!\n", len); goto err_unmap; } if (p + 2 > end) goto short_pkt; entry = p; } /* * Apparently some server sends responses that are a valid size, but * contain no entries, and have value_follows==0 and EOF==0. For * those, just set the EOF marker. */ if (!nr && entry[1] == 0) { dprintk("NFS: readdir reply truncated!\n"); entry[1] = 1; } out: kunmap_atomic(kaddr, KM_USER0); return nr; short_pkt: /* * When we get a short packet there are 2 possibilities. We can * return an error, or fix up the response to look like a valid * response and return what we have so far. If there are no * entries and the packet was short, then return -EIO. If there * are valid entries in the response, return them and pretend that * the call was successful, but incomplete. The caller can retry the * readdir starting at the last cookie. */ entry[0] = entry[1] = 0; if (!nr) nr = -errno_NFSERR_IO; goto out; err_unmap: nr = -errno_NFSERR_IO; goto out; } __be32 * nfs_decode_dirent(__be32 *p, struct nfs_entry *entry, int plus) { if (!*p++) { if (!*p) return ERR_PTR(-EAGAIN); entry->eof = 1; return ERR_PTR(-EBADCOOKIE); } entry->ino = ntohl(*p++); entry->len = ntohl(*p++); entry->name = (const char *) p; p += XDR_QUADLEN(entry->len); entry->prev_cookie = entry->cookie; entry->cookie = ntohl(*p++); entry->eof = !p[0] && p[1]; return p; } /* * NFS XDR decode functions */ /* * Decode simple status reply */ static int nfs_xdr_stat(struct rpc_rqst *req, __be32 *p, void *dummy) { int status; if ((status = ntohl(*p++)) != 0) status = nfs_stat_to_errno(status); return status; } /* * Decode attrstat reply * GETATTR, SETATTR, WRITE */ static int nfs_xdr_attrstat(struct rpc_rqst *req, __be32 *p, struct nfs_fattr *fattr) { int status; if ((status = ntohl(*p++))) return nfs_stat_to_errno(status); xdr_decode_fattr(p, fattr); return 0; } /* * Decode diropres reply * LOOKUP, CREATE, MKDIR */ static int nfs_xdr_diropres(struct rpc_rqst *req, __be32 *p, struct nfs_diropok *res) { int status; if ((status = ntohl(*p++))) return nfs_stat_to_errno(status); p = xdr_decode_fhandle(p, res->fh); xdr_decode_fattr(p, res->fattr); return 0; } /* * Encode READLINK args */ static int nfs_xdr_readlinkargs(struct rpc_rqst *req, __be32 *p, struct nfs_readlinkargs *args) { struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth; unsigned int replen; p = xdr_encode_fhandle(p, args->fh); req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); /* Inline the page array */ replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readlinkres_sz) << 2; xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, args->pgbase, args->pglen); return 0; } /* * Decode READLINK reply */ static int nfs_xdr_readlinkres(struct rpc_rqst *req, __be32 *p, void *dummy) { struct xdr_buf *rcvbuf = &req->rq_rcv_buf; struct kvec *iov = rcvbuf->head; size_t hdrlen; u32 len, recvd; char *kaddr; int status; if ((status = ntohl(*p++))) return nfs_stat_to_errno(status); /* Convert length of symlink */ len = ntohl(*p++); if (len >= rcvbuf->page_len) { dprintk("nfs: server returned giant symlink!\n"); return -ENAMETOOLONG; } hdrlen = (u8 *) p - (u8 *) iov->iov_base; if (iov->iov_len < hdrlen) { dprintk("NFS: READLINK reply header overflowed:" "length %Zu > %Zu\n", hdrlen, iov->iov_len); return -errno_NFSERR_IO; } else if (iov->iov_len != hdrlen) { dprintk("NFS: READLINK header is short. iovec will be shifted.\n"); xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen); } recvd = req->rq_rcv_buf.len - hdrlen; if (recvd < len) { dprintk("NFS: server cheating in readlink reply: " "count %u > recvd %u\n", len, recvd); return -EIO; } /* NULL terminate the string we got */ kaddr = (char *)kmap_atomic(rcvbuf->pages[0], KM_USER0); kaddr[len+rcvbuf->page_base] = '\0'; kunmap_atomic(kaddr, KM_USER0); return 0; } /* * Decode WRITE reply */ static int nfs_xdr_writeres(struct rpc_rqst *req, __be32 *p, struct nfs_writeres *res) { res->verf->committed = NFS_FILE_SYNC; return nfs_xdr_attrstat(req, p, res->fattr); } /* * Decode STATFS reply */ static int nfs_xdr_statfsres(struct rpc_rqst *req, __be32 *p, struct nfs2_fsstat *res) { int status; if ((status = ntohl(*p++))) return nfs_stat_to_errno(status); res->tsize = ntohl(*p++); res->bsize = ntohl(*p++); res->blocks = ntohl(*p++); res->bfree = ntohl(*p++); res->bavail = ntohl(*p++); return 0; } /* * We need to translate between nfs status return values and * the local errno values which may not be the same. */ static struct { int stat; int errno; } nfs_errtbl[] = { { NFS_OK, 0 }, { NFSERR_PERM, -EPERM }, { NFSERR_NOENT, -ENOENT }, { NFSERR_IO, -errno_NFSERR_IO}, { NFSERR_NXIO, -ENXIO }, /* { NFSERR_EAGAIN, -EAGAIN }, */ { NFSERR_ACCES, -EACCES }, { NFSERR_EXIST, -EEXIST }, { NFSERR_XDEV, -EXDEV }, { NFSERR_NODEV, -ENODEV }, { NFSERR_NOTDIR, -ENOTDIR }, { NFSERR_ISDIR, -EISDIR }, { NFSERR_INVAL, -EINVAL }, { NFSERR_FBIG, -EFBIG }, { NFSERR_NOSPC, -ENOSPC }, { NFSERR_ROFS, -EROFS }, { NFSERR_MLINK, -EMLINK }, { NFSERR_NAMETOOLONG, -ENAMETOOLONG }, { NFSERR_NOTEMPTY, -ENOTEMPTY }, { NFSERR_DQUOT, -EDQUOT }, { NFSERR_STALE, -ESTALE }, { NFSERR_REMOTE, -EREMOTE }, #ifdef EWFLUSH { NFSERR_WFLUSH, -EWFLUSH }, #endif { NFSERR_BADHANDLE, -EBADHANDLE }, { NFSERR_NOT_SYNC, -ENOTSYNC }, { NFSERR_BAD_COOKIE, -EBADCOOKIE }, { NFSERR_NOTSUPP, -ENOTSUPP }, { NFSERR_TOOSMALL, -ETOOSMALL }, { NFSERR_SERVERFAULT, -EREMOTEIO }, { NFSERR_BADTYPE, -EBADTYPE }, { NFSERR_JUKEBOX, -EJUKEBOX }, { -1, -EIO } }; /* * Convert an NFS error code to a local one. * This one is used jointly by NFSv2 and NFSv3. */ int nfs_stat_to_errno(int stat) { int i; for (i = 0; nfs_errtbl[i].stat != -1; i++) { if (nfs_errtbl[i].stat == stat) return nfs_errtbl[i].errno; } dprintk("nfs_stat_to_errno: bad nfs status return value: %d\n", stat); return nfs_errtbl[i].errno; } #define PROC(proc, argtype, restype, timer) \ [NFSPROC_##proc] = { \ .p_proc = NFSPROC_##proc, \ .p_encode = (kxdrproc_t) nfs_xdr_##argtype, \ .p_decode = (kxdrproc_t) nfs_xdr_##restype, \ .p_arglen = NFS_##argtype##_sz, \ .p_replen = NFS_##restype##_sz, \ .p_timer = timer, \ .p_statidx = NFSPROC_##proc, \ .p_name = #proc, \ } struct rpc_procinfo nfs_procedures[] = { PROC(GETATTR, fhandle, attrstat, 1), PROC(SETATTR, sattrargs, attrstat, 0), PROC(LOOKUP, diropargs, diropres, 2), PROC(READLINK, readlinkargs, readlinkres, 3), PROC(READ, readargs, readres, 3), PROC(WRITE, writeargs, writeres, 4), PROC(CREATE, createargs, diropres, 0), PROC(REMOVE, removeargs, stat, 0), PROC(RENAME, renameargs, stat, 0), PROC(LINK, linkargs, stat, 0), PROC(SYMLINK, symlinkargs, stat, 0), PROC(MKDIR, createargs, diropres, 0), PROC(RMDIR, diropargs, stat, 0), PROC(READDIR, readdirargs, readdirres, 3), PROC(STATFS, fhandle, statfsres, 0), }; struct rpc_version nfs_version2 = { .number = 2, .nrprocs = ARRAY_SIZE(nfs_procedures), .procs = nfs_procedures };